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Calculation of Pulse height distributions from deterministic transport simulations
In source-detector radiation transport simulations, pulse height distributions are a useful metric in assessing the effectiveness of nuclear instrumentation. In the area of spectroscopy, pulse height distributions are used to identify an unknown source. It is widely believed that pulse height distributions cannot be created using deterministic methods. This quantity is routinely calculated in Monte Carlo transport codes because each history is individually tracked and the amount of energy deposited by interaction events is easily tallied. We have developed a methodology to calculate the pulse height distribution using deterministic transport codes. The algorithm utilizes the scattered components of scalar flux which are readily calculated by iterating on the scattering source. The approach is applicable in three dimensions but we present here results from an implementation in 1D slab geometry with anisotropic scattering/angular quadrature orders up to P14/S32
Report on the September 2011 Meeting of the Next Generation Safegaurds Professional Network
The Next Generation Safeguards Professional Network (NGSPN) was established in 2009 by Oak Ridge National Laboratory targeted towards the engagement of young professionals employed in safeguards across the many national laboratories. NGSPN focuses on providing a mechanism for young safeguards professionals to connect and foster professional relationships, facilitating knowledge transfer between current safeguards experts and the next generation of experts, and acting as an entity to represent the interests of the international community of young and mid-career safeguards professionals. This is accomplished in part with a yearly meeting held at a national laboratory site. In 2011, this meeting was held at Pacific Northwest National Laboratory. This report documents the events and results of that meeting
MARS June 2012 Flight Data: Natural Background and Point Source Spectra
Abstract This brief document describes the electronic data that were collected by the Multi-sensor Aerial Radiation Survey (MARS) detector in June 2012 while mounted onboard the RSL Bell-412 helicopter. A copy of the data is included as an electronic appendix
Tumor-derived GDF-15 blocks LFA-1 dependent T cell recruitment and suppresses responses to anti-PD-1 treatment
Immune checkpoint blockade therapy is beneficial and even curative for some cancer patients. However, the majority don't respond to immune therapy. Across different tumor types, pre-existing T cell infiltrates predict response to checkpoint-based immunotherapy. Based on in vitro pharmacological studies, mouse models and analyses of human melanoma patients, we show that the cytokine GDF-15 impairs LFA-1/β2-integrin-mediated adhesion of T cells to activated endothelial cells, which is a pre-requisite of T cell extravasation. In melanoma patients, GDF-15 serum levels strongly correlate with failure of PD-1-based immune checkpoint blockade therapy. Neutralization of GDF-15 improves both T cell trafficking and therapy efficiency in murine tumor models. Thus GDF-15, beside its known role in cancer-related anorexia and cachexia, emerges as a regulator of T cell extravasation into the tumor microenvironment, which provides an even stronger rationale for therapeutic anti-GDF-15 antibody development
Preferences and Biases in Educational Choices and Labor Market Expectations: Shrinking the Black Box of Gender
Standard observed characteristics explain only part of the differences between men and women in education choices and labor market trajectories. Using an experiment to derive students' levels of overconfidence, and preferences for competitiveness and risk, this paper investigates whether these behavioral biases and preferences explain gender differences in college major choices and expected future earnings. In a sample of high ability undergraduates, we find that competitiveness and overconfidence, but not risk aversion, is systematically related with expectations about future earnings: individuals who are overconfident and overly competitive have significantly higher earnings expectations. Moreover, gender differences in overconfidence and competitiveness explain about 18% of the gender gap in earnings expectations. These experimental measures explain as much of the gender gap in earnings expectations as a rich set of control variables, including test scores and family background, and they are poorly proxied by these same control variables, underscoring that they represent independent variation. While expected earnings are related to college major choices, the experimental measures are not related with college major choice
Exotic state photoproduction
It is shown that the list of unusual mesons planned for a careful study in
photoproduction can be extended by the exotic states with which should be looked for in the decay
channels in the reactions and . The full classification of the states by their
quantum numbers is presented. A simple model for the spin structure of the , , and reaction amplitudes is formulated and the tentative estimates of the
corresponding cross sections at the incident photon energy
GeV are obtained: b, b, b, and b. The problem of the
signal extraction from the natural background due to the other production channels is discussed. In particular the estimates are
presented for the , , and reaction cross sections.
Our main conclusion is that the search for the exotic
states is quite feasible at JEFLAB facility. The expected yield of the events in a 30-day run at the 100% detection
efficiency approximates events.Comment: 19 pages, revtex, 1 figure in postscipt, some comments and references
added, a few minor typos corrected, to be published in Phys. Rev.
Binary systems and their nuclear explosions
Peer ReviewedPreprin
In Support of a Patient-Driven Initiative and Petition to Lower the High Price of Cancer Drugs
Comment in
Lowering the High Cost of Cancer Drugs--III. [Mayo Clin Proc. 2016]
Lowering the High Cost of Cancer Drugs--I. [Mayo Clin Proc. 2016]
Lowering the High Cost of Cancer Drugs--IV. [Mayo Clin Proc. 2016]
In Reply--Lowering the High Cost of Cancer Drugs. [Mayo Clin Proc. 2016]
US oncologists call for government regulation to curb drug price rises. [BMJ. 2015
Extrinsic Rewards and Intrinsic Motives: Standard and Behavioral Approaches to Agency and Labor Markets
Employers structure pay and employment relationships to mitigate agency problems. A large literature in economics documents how the resolution of these problems shapes personnel policies and labor markets. For the most part, the study of agency in employment relationships relies on highly stylized assumptions regarding human motivation, e.g., that employees seek to earn as much money as possible with minimal effort. In this essay, we explore the consequences of introducing behavioral complexity and realism into models of agency within organizations. Specifically, we assess the insights gained by allowing employees to be guided by such motivations as the desire to compare favorably to others, the aspiration to contribute to intrinsically worthwhile goals, and the inclination to reciprocate generosity or exact retribution for perceived wrongs. More provocatively, from the standpoint of standard economics, we also consider the possibility that people are driven, in ways that may be opaque even to themselves, by the desire to earn social esteem or to shape and reinforce identity
Connecting Planetary Composition with Formation
The rapid advances in observations of the different populations of
exoplanets, the characterization of their host stars and the links to the
properties of their planetary systems, the detailed studies of protoplanetary
disks, and the experimental study of the interiors and composition of the
massive planets in our solar system provide a firm basis for the next big
question in planet formation theory. How do the elemental and chemical
compositions of planets connect with their formation? The answer to this
requires that the various pieces of planet formation theory be linked together
in an end-to-end picture that is capable of addressing these large data sets.
In this review, we discuss the critical elements of such a picture and how they
affect the chemical and elemental make up of forming planets. Important issues
here include the initial state of forming and evolving disks, chemical and dust
processes within them, the migration of planets and the importance of planet
traps, the nature of angular momentum transport processes involving turbulence
and/or MHD disk winds, planet formation theory, and advanced treatments of disk
astrochemistry. All of these issues affect, and are affected by the chemistry
of disks which is driven by X-ray ionization of the host stars. We discuss how
these processes lead to a coherent end-to-end model and how this may address
the basic question.Comment: Invited review, accepted for publication in the 'Handbook of
Exoplanets', eds. H.J. Deeg and J.A. Belmonte, Springer (2018). 46 pages, 10
figure
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